Quantitative Aptitude - Arithmetic Ability Questions

If by selling an article for Rs. 390 a shopkeeper gains 20% , then the cost is

The rate of simple interest per annum at which a sum of money double itself in 16 2/3 yrs is

The simple and compound interest that can be earned in two years at the same rate is Rs 4000 and Rs 4180 respectively. What is the rate (percent per annum) of interest?

AB is a diameter of a circle. C is a point on the tangent drawn at A . If AB = 8 cm and AC = 6 cm , then the length of BC is

If a + b = 5 and ab = 6, then what is the value of a3 + b3?

25% discount is offered on an item. By applying a promo code a customer wins 10% cash back. What is the effective discount?

If a merchant offers a discount of 25% on the list price, then he makes a loss of 5%. What % profit or % loss will he make if he sells at a discount of 10% of the list price?